Switch logger to use Azure Monitor DCE API

[Arnavion]

The "Data Collector API" that logs directly to Log Analytics hasn't been updated since 2016, and there is an article about migrating to Azure Monitor's "Logs Ingestion API". The latter uses standard OAuth with SP credentials instead of the bespoke symmetric key method that the former uses.

https://learn.microsoft.com/en-us/azure/azure-monitor/logs/tutorial-logs-ingestion-portal

https://learn.microsoft.com/en-us/azure/azure-monitor/logs/custom-logs-migrate#migration-procedure

https://learn.microsoft.com/en-us/cli/azure/monitor/data-collection/rule

https://learn.microsoft.com/en-us/rest/api/monitor/data-collection-rules/create

[Arnavion]

Retirement notice: Transition to DCR-based custom log ingestion by 14 September 2026

Data Collector API will be retired on 14 September 2026 – transition to DCR-based custom log ingestion.

On 14 September 2026, we’ll retire Data Collector API for ingesting custom logs to Azure Monitor logs. Before that date, you’ll need to transition to the Data Collection Rules based log ingestion API

To avoid ingestion errors and data loss, transition to the DCR-based Log Ingestion API before 14 September 2026. Data Collector API endpoints will become unavailable after that date.